51²+260p+25
(p2−p+5)×(25p2+p−5) = p×2(25p×2+p-(-5))-p×(25×2+p-(-5))+5(25p×2+p-(-5)) = 100p²+2p²+10p-50p²-p²-5p+250p+5p+25 = 51²+260p+25
51²+260p+25
(p2−p+5)×(25p2+p−5) = p×2(25p×2+p-(-5))-p×(25×2+p-(-5))+5(25p×2+p-(-5)) = 100p²+2p²+10p-50p²-p²-5p+250p+5p+25 = 51²+260p+25